Wees in toilet but poos in knickers!

[theworldhasgoneinsane]

My DD will be 3 in October. We potty trained around April time and she got the wees straight away with very few accidents. However she still poos in her knickers! She knows when she's going to do it as she goes to the same spot in the house. I've tried trying to get her to keep sitting on the toilet or potty, reward chart, bribery! For a while she was holding it in and getting constipated, we managed to stop this and now she just happily poos in her knickers daily.
Her communication is really good and I'm sure she understands what she needs to do but I feel like she is making a choice to do this now!

Any ideas please?

@Ljordan13 thank you so much for replying! Aww pleased he’s sorted! She’s on lactulose now but sometimes that aspect is absolutely fine (nursery say it’s more than soft 🙈), I am sure she’s holding it though then hides and does it in her pants, multiple times in a day. I don’t know what else to do 😩 I’ve bought some toys to try bribery again!